Peppadews are substituted for the usual roasted red peppers in this riff on romesco.
Pulse Peppadews and brine, almonds, and garlic in a food processor until finely chopped. With machine running, add olive oil to form a loose paste.
Cook spaghetti in a pot of generously salted water until al dente. Drain pasta, reserving 1/2 cup pasta water, and toss both with Peppadew paste, salt, and pepper. Fold in feta and arugula.